Tectonic Development of the Japanese Islands Controlled by Philippine Sea Plate Motion

Strike-slip motion of a mega-splay fault system in the Nankai oblique subduction zone

“…The Philippine Sea Plate was subducting beneath the Japanese islands in the NNW direction at 15 Ma (Seno and Maruyama 1984;Takahashi 2006); this direction differs from the current plate motion direction (Miyazaki and Heki 2001;Ide et al 2010). The time of the change in subduction direction has not been determined precisely, but it was probably between 2 and 4 Ma (e.g., Kimura et al 2005;Takahashi 2006;Ikeda et al 2009). Therefore, the slip rate estimated in this study (approximately 20 mm/year) is not influenced by the change in plate subduction direction.…”

“…Although the Philippine Sea Plate currently subducts obliquely beneath the accretionary prism in the Nankai Trough (Seno et al 1993;Miyazaki and Heki 2001), it had subducted perpendicular to the trench until approximately 2 to 4 Ma (Kimura et al 2005;Takahashi 2006;Ikeda et al 2009). The change in plate motion reactivated some faults within the accretionary wedge as strike-slip faults that could accommodate trench-parallel shear strain due to the oblique plate subduction.…”

Integrated magnetobiochronology of the Pliocene–Pleistocene Miyazaki succession, southern Kyushu, southwest Japan: Implications for an Early Pleistocene hiatus and defining the base of the Gelasian (P/P boundary type section) in Japan

“…Slope failure may have resulted from deformation and collapse in a forearc basin. The Kurotaki unconformity, which separates the Miura and Kazusa Groups in the central part of the Boso Peninsula, has long been recognised as stratigraphically and tectonically significant (Koike, 1952;Niitsuma, 1976;Oda, 1975Oda, , 1977Takahashi, 2006). The Hisamine unconformity and the Kurotaki unconformity are of similar age (early Pleistocene in new age model).…”

Tectonic Process of the Sedimentary Basin Formation and Evolution in the Late Cenozoic Arc-Arc Collision Zone, Central Japan

“…By the way, due to the migration of trench triple junction, the moving direction of the Philippine Sea plate switched at 3Ma from the north direction to northwest [28], and, therefore, the colliding force against the border area between east and west Japan as well as the southern Fossa Magna should have weakened in comparison with the past. The contraction tectonics in the Japan Sea side could be attributed to starting of eastward motion of the Amur plate, because the start of the contractinal tectonics in the eastern margin of Japan Sea was significantly older than 3Ma.…”

“…In addition, the inversion process included locally the one of fault-slip sense where former normal faults trending north-south to northeast-southwest directions became re-activated as reverse faults (e.g., Kureha-yama fault: [66]). In the Hokuriku district of the Neogene sedimentary basins, however, alluvial plains continue their sedimentation without performing "basin inversion" like the Miocene Shin'etsu sedimentary basin, where the whole area of subsidence with thick sedimentary layers had changed reversely into the upheaval zone [27][28][29].…”